/**
 *WangGANG
 *2018/7/24
 */
package main

import (
	"fmt"
	"os"
)

func main() {
	fmt.Println("$GOROOT")
	fmt.Println(os.ExpandEnv("$GOROOT"))
	fmt.Println(os.ExpandEnv("$GOPATH"))
	fmt.Println(os.Getenv("GOROOT"))
	fmt.Println(os.Hostname())

}
